VARIATIONS OF MILK CONSTITUENTS 



175 



curs ; and then the ratio remains uniform during the 

 rest of the season, which extends approximately 

 through the seventh or eighth month of lactation. 



The general statement has been prominently cur- 

 rent in literature to the effect that casein and albumin 

 are present in cow's milk in very constant relative pro- 

 portions, the amount of casein being five times that of 

 albumin. In the case of herd milks, we have found 

 casein varying all the way from 2.6 to 5.6 parts for 

 one part of albumin. In single milkings of individual 

 cows, the variations are considerably wider. 



AVERAGE COMPOSITION FACTORY MILK 



The following figures represent the average 

 monthly composition of milk as obtained at cheese- 

 factories in New York state. These data repre- 

 sent the work of several seasons and are taken 

 from the records of the New York experiment 

 station : 



Month 



Solids 



Fat 



Casein 



Albumin 



Sugar 

 ash. etc. 



April 



May 



June 



July 



August . . . . 

 September. 

 October. . . 



Average . . . 



5.74 

 5.83 

 5.76 

 5.83 

 5.79 

 5.68 

 5.72 



5.78 



The following figures show the extreme variaiions 

 in composition of cheese-factory milk during the 

 season : 



